The present invention relates to intraventricular placement of a ventricular assist device, to components useful in such devices, and to methods of using the same.
In certain disease states, the heart lacks sufficient pumping capacity to meet the needs of the body. This inadequacy can be alleviated by providing a mechanical pumping device referred to as a ventricular assist device (“VAD”) to supplement the pumping action of the heart. Considerable effort has been devoted to providing a VAD which can be implanted and which can remain in operation for months or years to keep the patient alive while the heart heals, or which can remain in operation permanently or until a suitable donor heart becomes available if the heart does not heal.
The VAD is typically connected to the heart, most commonly to the left ventricle. For example, a VAD may include a pump which is installed in the body outside of the heart. The VAD may have an inlet cannula connected to the interior of the left ventricle and connected to the intake of the pump. The VAD may also include an outlet tube connected between the outlet of the pump and the aorta. Once connected, the VAD and the heart both pump blood from the left ventricle to the aorta.
As described, for example, in U.S. Pat. Nos. 5,376,114 and 6,217,541 certain VADs having pumps are arranged so that at least a portion of the pump is disposed within the heart when the VAD is implanted within the patient. These VADs incorporate pumps which are connected to separate electric motors by elongated driveshafts. Such shaft-driven pumps suffer from significant drawbacks. Commonly assigned, copending U.S. patent application Ser. No. 12/072,471, the disclosure of which is hereby incorporated by reference herein, discloses a VAD having a unitary pump and motor adapted for positioning within the arterial system as, for example, within the aorta.
Despite the considerable effort devoted to improvements in VADs, still further improvement would be desirable.